[Oilpan] Move ScrollAnimators onto oilpan heap

third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h

Index: third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h
diff --git a/third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h b/third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h
index 0917eeaada4fa4c25e58eccbaba96d9279f78863..ed9d5236e40265031960ec3b3a025daedbb402c3 100644
--- a/third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h
+++ b/third_party/WebKit/Source/platform/scroll/ScrollAnimatorBase.h
@@ -44,11 +44,12 @@ class FloatPoint;
 class ScrollableArea;
 class Scrollbar;
 
-class PLATFORM_EXPORT ScrollAnimatorBase {
+class PLATFORM_EXPORT ScrollAnimatorBase : public GarbageCollectedFinalized<ScrollAnimatorBase> {
 public:
-    static PassOwnPtr<ScrollAnimatorBase> create(ScrollableArea*);
+    static ScrollAnimatorBase* create(ScrollableArea*);
 
     virtual ~ScrollAnimatorBase();
+    virtual void cleanup() { }
 
     // Computes a scroll destination for the given parameters.  The returned
     // ScrollResultOneDimensional will have didScroll set to false if already at
@@ -99,13 +100,15 @@ public:
     virtual void notifyContentAreaScrolled(const FloatSize&) { }
 
     virtual bool setScrollbarsVisibleForTesting(bool) { return false; }
+
+    DECLARE_VIRTUAL_TRACE();
+
 protected:
     explicit ScrollAnimatorBase(ScrollableArea*);
 
     virtual void notifyPositionChanged();
 
-    GC_PLUGIN_IGNORE("509911")
-    ScrollableArea* m_scrollableArea;
+    RawPtrWillBeMember<ScrollableArea> m_scrollableArea;

[haraken, 2015/12/03 05:34:35]

In non-oilpan, this raw pointer has a risk of becoming a stale pointer (if the
ScrollableArea gets destructed before the next GC collects the
ScrollAnimatorBase).

Sorry about getting you back and forth, but I'd suggest making ScrollableArea
NoBaseWillBeGarbageCollected (not GarbageCollected). Then the risk will be gone.
Also you don't need to call cleanup() only in non-oilpan when the ScrollableArea
gets destructed.

[peria, 2015/12/03 09:24:25]

Done.

     float m_currentPosX; // We avoid using a FloatPoint in order to reduce
     float m_currentPosY; // subclass code complexity.